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/***************************************************************************/
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/* Type 1 parser (body). */
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/* Copyright 1996-2001, 2002, 2003, 2004, 2005, 2008, 2009 by */
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/* David Turner, Robert Wilhelm, and Werner Lemberg. */
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/* This file is part of the FreeType project, and may only be used, */
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/* modified, and distributed under the terms of the FreeType project */
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/* license, LICENSE.TXT. By continuing to use, modify, or distribute */
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/* this file you indicate that you have read the license and */
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/* understand and accept it fully. */
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/***************************************************************************/
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/*************************************************************************/
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/* The Type 1 parser is in charge of the following: */
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/* - provide an implementation of a growing sequence of objects called */
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/* a `T1_Table' (used to build various tables needed by the loader). */
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/* - opening .pfb and .pfa files to extract their top-level and private */
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/* - read numbers, arrays & strings from any dictionary. */
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/* See `t1load.c' to see how data is loaded from the font file. */
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/*************************************************************************/
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#include FT_INTERNAL_DEBUG_H
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#include FT_INTERNAL_STREAM_H
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#include FT_INTERNAL_POSTSCRIPT_AUX_H
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/*************************************************************************/
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/* The macro FT_COMPONENT is used in trace mode. It is an implicit */
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/* parameter of the FT_TRACE() and FT_ERROR() macros, used to print/log */
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/* messages during execution. */
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#define FT_COMPONENT trace_t1parse
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/*************************************************************************/
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/*************************************************************************/
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/*************************************************************************/
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/***** INPUT STREAM PARSER *****/
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/*************************************************************************/
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/*************************************************************************/
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/*************************************************************************/
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/* see Adobe Technical Note 5040.Download_Fonts.pdf */
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read_pfb_tag( FT_Stream stream,
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if ( !FT_READ_USHORT( tag ) )
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if ( tag == 0x8001U || tag == 0x8002U )
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if ( !FT_READ_ULONG_LE( size ) )
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check_type1_format( FT_Stream stream,
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const char* header_string,
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size_t header_length )
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if ( FT_STREAM_SEEK( 0 ) )
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error = read_pfb_tag( stream, &tag, &dummy );
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/* We assume that the first segment in a PFB is always encoded as */
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/* text. This might be wrong (and the specification doesn't insist */
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/* on that), but we have never seen a counterexample. */
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if ( tag != 0x8001U && FT_STREAM_SEEK( 0 ) )
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if ( !FT_FRAME_ENTER( header_length ) )
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if ( ft_memcmp( stream->cursor, header_string, header_length ) != 0 )
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error = T1_Err_Unknown_File_Format;
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FT_LOCAL_DEF( FT_Error )
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T1_New_Parser( T1_Parser parser,
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PSAux_Service psaux )
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psaux->ps_parser_funcs->init( &parser->root, 0, 0, memory );
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parser->stream = stream;
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parser->base_len = 0;
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parser->base_dict = 0;
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parser->private_len = 0;
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parser->private_dict = 0;
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parser->in_memory = 0;
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parser->single_block = 0;
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/* check the header format */
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error = check_type1_format( stream, "%!PS-AdobeFont", 14 );
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if ( error != T1_Err_Unknown_File_Format )
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error = check_type1_format( stream, "%!FontType", 10 );
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FT_TRACE2(( "[not a Type1 font]\n" ));
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/******************************************************************/
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/* Here a short summary of what is going on: */
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/* When creating a new Type 1 parser, we try to locate and load */
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/* the base dictionary if this is possible (i.e., for PFB */
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/* files). Otherwise, we load the whole font into memory. */
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/* When `loading' the base dictionary, we only setup pointers */
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/* in the case of a memory-based stream. Otherwise, we */
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/* allocate and load the base dictionary in it. */
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/* parser->in_pfb is set if we are in a binary (`.pfb') font. */
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/* parser->in_memory is set if we have a memory stream. */
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/* try to compute the size of the base dictionary; */
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/* look for a Postscript binary file tag, i.e., 0x8001 */
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if ( FT_STREAM_SEEK( 0L ) )
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error = read_pfb_tag( stream, &tag, &size );
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if ( tag != 0x8001U )
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/* assume that this is a PFA file for now; an error will */
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/* be produced later when more things are checked */
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if ( FT_STREAM_SEEK( 0L ) )
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/* now, try to load `size' bytes of the `base' dictionary we */
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/* found previously */
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/* if it is a memory-based resource, set up pointers */
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parser->base_dict = (FT_Byte*)stream->base + stream->pos;
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parser->base_len = size;
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parser->in_memory = 1;
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/* check that the `size' field is valid */
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if ( FT_STREAM_SKIP( size ) )
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/* read segment in memory -- this is clumsy, but so does the format */
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if ( FT_ALLOC( parser->base_dict, size ) ||
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FT_STREAM_READ( parser->base_dict, size ) )
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parser->base_len = size;
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parser->root.base = parser->base_dict;
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parser->root.cursor = parser->base_dict;
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parser->root.limit = parser->root.cursor + parser->base_len;
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if ( error && !parser->in_memory )
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FT_FREE( parser->base_dict );
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T1_Finalize_Parser( T1_Parser parser )
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FT_Memory memory = parser->root.memory;
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/* always free the private dictionary */
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FT_FREE( parser->private_dict );
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/* free the base dictionary only when we have a disk stream */
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if ( !parser->in_memory )
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FT_FREE( parser->base_dict );
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parser->root.funcs.done( &parser->root );
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FT_LOCAL_DEF( FT_Error )
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T1_Get_Private_Dict( T1_Parser parser,
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PSAux_Service psaux )
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FT_Stream stream = parser->stream;
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FT_Memory memory = parser->root.memory;
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FT_Error error = T1_Err_Ok;
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if ( parser->in_pfb )
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/* in the case of the PFB format, the private dictionary can be */
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/* made of several segments. We thus first read the number of */
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/* segments to compute the total size of the private dictionary */
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/* then re-read them into memory. */
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FT_Long start_pos = FT_STREAM_POS();
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parser->private_len = 0;
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error = read_pfb_tag( stream, &tag, &size );
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if ( tag != 0x8002U )
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parser->private_len += size;
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if ( FT_STREAM_SKIP( size ) )
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/* Check that we have a private dictionary there */
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/* and allocate private dictionary buffer */
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if ( parser->private_len == 0 )
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FT_ERROR(( "T1_Get_Private_Dict:"
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" invalid private dictionary section\n" ));
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error = T1_Err_Invalid_File_Format;
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if ( FT_STREAM_SEEK( start_pos ) ||
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FT_ALLOC( parser->private_dict, parser->private_len ) )
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parser->private_len = 0;
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error = read_pfb_tag( stream, &tag, &size );
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if ( error || tag != 0x8002U )
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if ( FT_STREAM_READ( parser->private_dict + parser->private_len,
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parser->private_len += size;
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/* We have already `loaded' the whole PFA font file into memory; */
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/* if this is a memory resource, allocate a new block to hold */
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/* the private dict. Otherwise, simply overwrite into the base */
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/* dictionary block in the heap. */
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/* first of all, look at the `eexec' keyword */
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FT_Byte* cur = parser->base_dict;
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FT_Byte* limit = cur + parser->base_len;
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if ( c == 'e' && cur + 9 < limit ) /* 9 = 5 letters for `eexec' + */
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/* newline + 4 chars */
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if ( cur[1] == 'e' &&
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FT_ERROR(( "T1_Get_Private_Dict:"
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" could not find `eexec' keyword\n" ));
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error = T1_Err_Invalid_File_Format;
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/* check whether `eexec' was real -- it could be in a comment */
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/* or string (as e.g. in u003043t.gsf from ghostscript) */
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parser->root.cursor = parser->base_dict;
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parser->root.limit = cur + 9;
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cur = parser->root.cursor;
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limit = parser->root.limit;
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while ( cur < limit )
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if ( *cur == 'e' && ft_strncmp( (char*)cur, "eexec", 5 ) == 0 )
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T1_Skip_PS_Token( parser );
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if ( parser->root.error )
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T1_Skip_Spaces ( parser );
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cur = parser->root.cursor;
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/* we haven't found the correct `eexec'; go back and continue */
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limit = parser->base_dict + parser->base_len;
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/* now determine where to write the _encrypted_ binary private */
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/* dictionary. We overwrite the base dictionary for disk-based */
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/* resources and allocate a new block otherwise */
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parser->root.limit = parser->base_dict + parser->base_len;
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T1_Skip_PS_Token( parser );
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cur = parser->root.cursor;
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/* according to the Type1 spec, the first cipher byte must not be */
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/* an ASCII whitespace character code (blank, tab, carriage return */
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/* or line feed). We have seen Type 1 fonts with two line feed */
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/* characters... So skip now all whitespace character codes. */
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while ( cur < limit &&
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FT_ERROR(( "T1_Get_Private_Dict:"
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" `eexec' not properly terminated\n" ));
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error = T1_Err_Invalid_File_Format;
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size = parser->base_len - ( cur - parser->base_dict );
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if ( parser->in_memory )
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/* note that we allocate one more byte to put a terminating `0' */
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if ( FT_ALLOC( parser->private_dict, size + 1 ) )
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parser->private_len = size;
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parser->single_block = 1;
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parser->private_dict = parser->base_dict;
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parser->private_len = size;
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parser->base_dict = 0;
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parser->base_len = 0;
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/* now determine whether the private dictionary is encoded in binary */
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/* or hexadecimal ASCII format -- decode it accordingly */
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/* we need to access the next 4 bytes (after the final \r following */
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/* the `eexec' keyword); if they all are hexadecimal digits, then */
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/* we have a case of ASCII storage */
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if ( ft_isxdigit( cur[0] ) && ft_isxdigit( cur[1] ) &&
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ft_isxdigit( cur[2] ) && ft_isxdigit( cur[3] ) )
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/* ASCII hexadecimal encoding */
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parser->root.cursor = cur;
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(void)psaux->ps_parser_funcs->to_bytes( &parser->root,
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parser->private_dict,
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parser->private_len = len;
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/* put a safeguard */
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parser->private_dict[len] = '\0';
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/* binary encoding -- copy the private dict */
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FT_MEM_MOVE( parser->private_dict, cur, size );
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/* we now decrypt the encoded binary private dictionary */
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psaux->t1_decrypt( parser->private_dict, parser->private_len, 55665U );
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/* replace the four random bytes at the beginning with whitespace */
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parser->private_dict[0] = ' ';
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parser->private_dict[1] = ' ';
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parser->private_dict[2] = ' ';
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parser->private_dict[3] = ' ';
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parser->root.base = parser->private_dict;
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parser->root.cursor = parser->private_dict;
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parser->root.limit = parser->root.cursor + parser->private_len;